1. Field of the Invention
The present invention relates to a numerical controller having a multi-path control function, and more particularly to a numerical controller which can display programs of each path in parallel, and edit them.
2. Description of the Related Art
In a numerical device which can control a plurality of paths, a plurality of processing steps can be simultaneously or continuously performed by operating machines, such as machine tools, while synchronizing with the paths, executing programs for each path respectively. To edit the processing programs selected by each path in a numerical controller which can control multi-paths according to a prior art, a target path of editing is switched, synchronization conditions are visually checked, and the target path is individually edited.
As a method for displaying the programs of each path on a display device, a method for displaying the programs of each path in parallel, or a method for displaying them in serial, is known. In the case of a parallel display, a method of displaying the programs of each path in parallel, in association with the respective time, so that the time relationship is recognized is known, and in the case of a serial display, a method of displaying multi-path control and single control, which coexist in one processing program, in serial, is known, as disclosed in Japanese Patent Application Laid-Open No. 2000-122709.
In the case of editing programs in each path, which requires cooperatively and simultaneously moving the axes controlled by a plurality of paths by program instructions in each path, it is necessary to recognize the execution sequence of program instructions in each path, and edit while confirming the relationships of synchronization, execution and queuing among the paths. However, if a method for displaying the programs of each path in serial is used, recognizing the time relationships among paths is difficult, hence editing thereof is difficult. Even if the programs of each path are displayed in parallel, it is difficult to recognize the time relationships of complicated synchronization, execution and queuing among paths if the programs are merely displayed in parallel. Therefore as the above mentioned Japanese Patent Application Laid-Open No. 2000-122709 discloses, a method for displaying the programs of each path in parallel and displaying the time relationship in association with queuing codes, so that the time relationships can be easily understood, has been proposed, but in the case of this method, blanks increase and portions to display programs decreases, therefore the editing operation becomes difficult.